Dissecting Suppressor Cell Development

The development of a population of 'regulatory' immune cells is more complicated than originally thought, according to a paper to be published online in Nature Immunology. Regulatory T cells - Treg cells - suppress the activity of auto-aggressive immune cells and prevent the onset of catastrophic autoimmunity. Mice and humans expressing a mutant version of the protein Foxp3 contain few Treg cells and suffer from severe autoimmune pathology, suggesting that Foxp3 is essential for Treg cell development.

Talal Chatila and colleagues used a clever strategy to 'track' cells expressing a mutant version of the Foxp3 protein, and noted that although the cells were unable to suppress autoimmune activity as expected, they still developed many other typical Treg cell characteristics. The identity of another protein or proteins capable of driving these aspects of Treg cell development requires further investigation.